Post Processing to affect only the 3D scene content, leaving the AR background unaffected

In my project (Unity 2022.3.42f1, URP, using ARKit), I’m having trouble managing post-processing on the AR camera background. The issue is that post-processing effects are being applied to the AR background as well, which makes it look worse. However, the 3D scene itself really benefits from post-processing, so I can’t simply turn it off altogether.

I tried using a camera stack, where the AR background camera is set as the first camera. But, since the second camera in the stack automatically applies its post-processing to everything (including the AR background), this didn’t solve the issue.

I also attempted creating an inverted post-processing volume on the first camera (for just the AR background) to approximate the original camera feed after both layers of post-processing are applied. Unfortunately, there’s another problem with camera stacking in URP when using AR—any stacked cameras render with a significant offset from the main camera, which disrupts tracking accuracy and makes the AR experience unusable.

My goal: I want post-processing to affect only the 3D scene content, leaving the AR background unaffected.

Has anyone found a workaround for applying post-processing exclusively to the 3D scene in URP with ARKit?

Note that in general we don’t recommend post-processing due to performance limitations of XR apps.

What you’re trying to do should be possible, but it’s not really an AR Foundation question. I recommend that you tag this post as URP instead.

1 Like

Hi,

Did you happen to find a solution for this by any chance?

Thanks!

Chris